Abstract
We modeled the evolution of the Milky Way Galaxy to trace the distribution in space and time of four prerequisites for complex life: the presence of a host star, enough heavy elements to form terrestrial planets, sufficient time for biological evolution, and an environment free of life-extinguishing supernovae. We identified the Galactic habitable zone (GHZ) as an annular region between 7 and 9 kiloparsecs from the Galactic center that widens with time and is composed of stars that formed between 8 and 4 billion years ago. This GHZ yields an age distribution for the complex life that may inhabit our Galaxy. We found that 75% of the stars in the GHZ are older than the Sun.
| Original language | English |
|---|---|
| Pages (from-to) | 59-62 |
| Number of pages | 4 |
| Journal | Science |
| Volume | 303 |
| Issue number | 5654 |
| DOIs | |
| Publication status | Published - 2004 |
| Externally published | Yes |